Treating the most serious cases of COVID-19 calls for the use of ventilators. We’ve all heard this, and also that there is a shortage of these devices. But there is not one single type of ventilator, and that type of machine is not the only option when it comes to assisted breathing being used in treatment. Information is power and having better grasp on this topic will help us all better understand the situation.
We recently wrote about a Facebook group focused on open source ventilators and other technology that could assist in the COVID-19 pandemic. There was an outpouring of support, and while the community is great when it comes to building things, it’s clear we all need more information about the problems doctors are currently dealing with, and how existing equipment was designed to address them.
It’s a long and complicated topic, though, so go get what’s left of your quarantine snacks and let’s dig in.
Continue reading “Ventilators 101: What They Do And How They Work”
Continuous Positive Airway Pressure machines are a common treatment tool for sleep apnea and other respiratory issues. A common problem with their use is that the mask becomes dislodged during sleep, and thus fails to provide airway pressure to the patient. [Bin Sun] decided to take a stab at solving this problem.
The project consists of an Arduino fitted with a MPXV7002DP pressure sensor. The sensor is used to monitor the pressure in the CPAP pipes. If the pressure varies regularly, it is likely the system is working. If however, the pressure remains at a roughly constant level, that suggests the mask is no longer properly fitted to the wearer, or that there is another problem. In this event, the device sounds a buzzer to wake the wearer, alerting them to check the equipment.
It’s a simple solution to the problem, and something we’re surprised isn’t built into most CPAP machines from the factory. It’s important to be careful before modifying any medical equipment, though we see plenty of hackers taking the plunge to innovate in this area.
Preterm infants frequently require ventilator support while they’re in the neonatal ICU, and this is usually done with a CPAP machine. The machine to infant interface is called a nasal cannula, a bit of plastic that connects an infant’s nose to the machine. Because there aren’t that many sizes of nasal cannula available, and preemies come in all sizes, there are inevitable problems. Ill-fitting nasal cannula can reduce the effectiveness of a CPAP, and can even cause significant damage to an infant’s septum.
For his Hackaday Prize entry, [Ben] is tackling this problem head on. He’s working on creating individualized nasal cannula for newborns using 3D modeling and printing, allowing nasal cannula of all shapes and sizes to be created in a matter of hours.
To create these customized cannula, [Ben] is 3D scanning an infant mannequin head to gather enough data to import it into a Processing sketch. A custom cannula is then created and printed with flexible 3D printer filament. In theory, it should work, apart from the considerations involved in building a medical device.
As for why custom plastic tubes matter, [Ben] works at the only NICU in Western Australia. Even though he only sees 8-10 CPAP ‘pressure injuries’ in his unit each year, these kids are extremely fragile and some parents have expressed a desire for something that isn’t as uncomfortable for their newborn than the off-the-shelf solution. Customizing these cannula from a quick 3D scan is a great way to do that, and a perfect example of the Hackaday Prize theme of ‘build something that matters.’
One of our avid readers named [Felix] suffers from sleep apnea, and needs a CPAP machine in order to not suffocate while he sleeps — After a recent power-outage, his machine broke, so he decided to try his hand at fixing it.
A CPAP (Continuous Positive Airway Pressure) machine ensures people suffering from sleep apnea breath throughout the night, by preventing their throats from closing. As a medical device, they tend to be super expensive, which is why [Felix] wanted to try fixing his (at least until he gets a new machine covered by insurance).
Upon opening up the machine, it was easy to see the problem: the circuit board was completely fried. Luckily, the machine is pretty simple. It has a brushless DC motor (12V), and two chambers with air filters, along with an air pressure sensor. Since the motor is brushless, it’s not quite as simple as just hooking it up to a power supply. It had a whopping 8 separate leads.
Continue reading “Hacking Out Of Necessity — Fixing Your Own CPAP Machine”